In the aviation field, the range of application of composite materials such as, for example, carbon fiber reinforced plastics (CFRP) has extended to the primary structure. Also, utilizing the advantage of light weight of composite materials, it is desirable that joints do not use fasteners, in order to achieve weight reduction of the structure.
The so-called pi (π) shaped joint in which a groove is formed and a member (for example a plate member) is inserted into the groove is an example of a joint.
A plate member inserted into the joint is bonded using adhesive, and the joint is also bonded to a preform using adhesive. In this way, plate members are connected to a preform.
Also, when assembling the structure, plate members that are joined to the preform must be positioned with high accuracy. In other words, if the joint is provided in advance on the preform, it is necessary to position the plate member with respect to the joint with high accuracy.
In Patent Document 1, a peg (projection) for positioning is provided on a side face of a plate member, and a slot into which the peg is fitted is provided on a side face of a joint, and positioning is carried out by inserting the plate member so that the peg of the plate member is fitted into the slot of the joint.